Americans are just very obstinate about those things. It's like the Windows of metrology - backwards compatibility trumps everything else, even when you have utterly bonkers things like ounces vs fluid ounces.
Using French Revolutionary units doesn’t really matter in STEM, either: one can conduct science just as well in any units one wishes. One unit of measure is not more scientific than another. For example, degrees Kelvin and Rankine measure the same thing with different units. If anything, the Rankine degrees are more precise!
Anyway, the French system isn't what people mean by "metric" in this context, they mean the SI system of units, and so in practice it's not so much that it wouldn't matter which you choose as that you don't have any option except SI.
If you wanted an independent system of units you'd need to do a lot of expensive metrication, and in practice Americans are too cheap for that, so the US "customary" units are just aliases for so-and-so-much amount of some SI unit, they aren't actually independent at all.
The reason people focus on metric is that for everyday people that's the part which jumps out as more intuitive. All these nice powers of 10, very tidy.
For T&E it really matters see NASA's Mars Climate Orbiter and the need for heroics in the Gimli glider.
You need to keep to the same unit.
> You need to keep to the same unit.
Completely agreed. You’ll get similar issues if you have one set of parts using m/s and others using km/hr.
And you’ll avoid those issues with any standard, whether it’s m/s, knots or mph. The important thing is to have a standard.
It's not just obstinance, switching everything to metric in the US would likely cost billions (if not trillions) of dollars. And other countries that have made the switch have often ended up with weird Frankensystems of measurement, like the UK where they mix metric and imperial all the time (plus the weird UK-specific measurements they have like "stone", which is based on the pound).
Anything to do with STEM is metric.
Milk is also allowed to be sold in pints, traditionally glass bottle re-usable milk bottles were one pint.
It is also usual (but not legal) to sell a pint or a half of various soft drinks, in theory you should be sold these in some other way, I always say "large" or "small" but in practice ordinary people say "pint" and after all the staff will probably more or less fill a pint glass so, whatever.
Spirits (e.g. gin) are measured in either 25ml or 35ml shots. An establishment can choose either, post which one they picked and use that consistently. Why two seemingly unrelated sizes? Well, historically there were two different non-metric sizes permitted in law, and when the government legislated to make these SI units there were lobbyists demanding they allow this to continue despite the opportunity to rationalize.
As in the US, containers you purchase in a store are labelled, but here the labels must prominently show SI volume units and EU-style value metrics are required on shelf markings, so e.g. 10p per 100ml of Coke is a good price, maybe the Pepsi is on a deal for 9.5p per 100ml, the store's terrible own brand is 5p per 100ml. This EU strategy prevents people screwing with sizes to make you think you're getting a better deal, that cheaper bottle may look like a good idea but hey, it's 18p per 100ml, ah, it's slimmer in the middle which makes it actually much smaller than it looks.
https://en.wikipedia.org/wiki/Metrication_in_the_United_Stat...
One does have to wonder what it is about Anglo countries specifically that makes it so difficult for them, though. Well, Canada at least has the excuse of being next door to US, with the resulting economic effects. For UK I'm pretty sure it's just about not being like "the Continent" at this point.
A huge percentage of those countries didn't have established industrial bases, infrastructure, etc. And also no educated general populace that needed reeducating. And often those countries were effectively forced into adopting metric through colonization and/or invasion.
People get very worked up about it too. People got very worked up about a government proposal to allow people to put imperial units on food in larger type than metric (at the moment it has to be metric larger - or at least the same size).
Everything in engineering and science has been entirely metric since the 80s.
OTOH on road sings, US at least seems to be using miles alone consistently, so you end up with labels like "1 3/4 miles" every now and then, which I find to be difficult to parse quickly.
I tend to think in metres at that scale but a yard is near enough.
Some of those "Metric martyr" types, the kind of people who think anything which changed after they were 35 is an abomination, but somehow anything which changed ten years before they were born has never been any other way, will vandalize legal stuff which uses (in their opinion) the wrong units. So if you put a (legal and reasonable) 1.5km distance sign on a cycle route, but some car driver who thinks sane units are fascism sees it, they might smash it to pieces which is annoying.
There has been a very gradual lean towards sanity, after all my mother was taught decimal currency because it was forthcoming when she was at school, her parents had used a non-decimal currency system. When I was a teenager I still had coins which, though they were treated as their modern decimal value, if you read their faces had a non-decimal value printed on them, because it's too expensive to replace the currency when you switch.
When I was a child I would buy a quarter pound of sweets. At the turn of the century I'd ask for, and receive, 100 grams or 200 grams as I felt, but most customers would use pounds (although legally they'd be served in grams). These days everybody else would likely also ask in grams. So it's changing, it's just very slow.
What's clumsy about 30cm though? If you are working at scales where this level of precision is needed, you can just use cm throughout, and the beauty of metric is that even someone who has never had to do that before will know immediately how much it is because conversion to meters (or millimeters, or whatever the primary unit is in their usual applications) is so easy.
Similarly, I've heard similar sentiments expressed about lack of pound equivalent in metric. But in practice we just say "500 grams" etc (and for bonus points you get 400 grams, 300 grams etc).
Miles and yards are both used as units of distance, so conversion is obviously relevant. The only reason why "yards in a mile" doesn't come up all the time is because Americans work around it by subconsciously (?) avoiding any such cases where the conversion is non-trivial. E.g. a road sign in Europe might say "400 m", whereas in US a similar one will be "1/4 miles".
And "evolved from hundreds years of usage" generally means a lack of internal consistency, because most units originated a long time ago as a way to measure something very specific - in many cases, something completely irrelevant to most people using those units today. Nor did those units remain consistent through history - just look at how many definitions ounce has in US in different contexts, all of them historical! Or regular vs nautical vs survey mile. Even just cleaning up that mess would be a massive improvement.
This is where we disagree. It would be a small improvement at best. Most of what you're pointing out are the awkward corner cases that just don't come up or, like you said, we already have other solutions for. Outside of some specialties, pretty much no one needs to know how many cups are in a gallon or yards in a mile or what a nautical mile is. I don't know those things, and I somehow get by OK.
These are conversions I know off the top of my head, I didn't need to look them up. Which is the point the GP was making: it's not hard to memorize the handful of conversions you will encounter in everyday life. Most people living here did it as children and have never had to think about it since. That's why there's no actual gain for us to switch to metric units. On the other hand there would be quite a bit of pain as everyone had to adjust to estimating things in kilos vs pounds, grams vs cups (in recipes), and so on. So for the typical American, it is actually a net negative for the country to switch to the metric system. It isn't just stubbornness.
This is not true and that's trivially verifiable.
No calculator, no references, no Google:
How many inches are in 5 and three-quarter miles?
How much does 5 & 3/4 gallons of water weigh?
The point is that it is easy to interconvert units in the metric system: they're all interrelated and all of them can be expressed in terms of other units.
A litre is the volume of a cube that is 10x10x10cm. A cubic cm of water weighs a gram. Therefore, 10 cubic cm of water weighs 1kg. In other words, a kilo is the weight of a litre of water.
It takes 1 calorie of energy to heat 1g of water by 1ºC. So to heat a litre by one degree takes 1000 calories, or 1 kilocalorie. To boil it, you need to raise its temperature to 100 degrees, because that's the boiling point of water. From room temperature of say 20º that means
100-20 = 80 80 x 1000 = 80,000 80 kcal
This is useful. You can work out how much energy you need, using a pencil and paper.
This makes it easy to convert. Units that are easier to convert are more useful.
Whereas, as Josh Bazell put it:
« Whereas in the American system, the answer to ‘How much energy does it take to boil a room-temperature gallon of water?’ is ‘Go fuck yourself,’ because you can’t directly relate any of those quantities. »
That's stupid. They can easily be related, but the people who devised this batshit set of scaled random numbers a few centuries ago didn't think of it.
It's not "what you're used to is better".
It's "one system is easier to work with than the other, and lets you do things the other system does not permit you to do."
Metric is objectively, demonstrably better than imperial.
And the common response of "oh but my system is what people feel" is also total bullshit, because that is 100% what you're used to.
A warmish day is feels like 20º to me. A hot day feels like 30º. A burning can't think straight day is 40º. Below freezing is below zero: it's simple and intuitive.
Except they didn't actually, see my points about the UK (similar points apply to Canada).
And sure, of course metric isn't necessary. You can also write all software in COBOL and PL/I. But over the long term, the convenience of having a self-consistent system based on a few simple principles rather than historical precedent adds up.
That's the missing link for Americans.
Much to my surprise, a random check of a US-based office supply company shows that they do have A4 in stock -- at a price about 40% higher than letter-sized.
Hacker News users may be familiar with Julia Evans (http://jvns.ca) who creates technology zines that work in both A4 and Letter sizes, folded in half.
This one surprised me quite a bit. I think most people have A4/letter-sized folders. Why does anyone think that papers slightly longer than those folders are a good idea?
Legal folders can be great to be able to print letter-sized things on, then you have an area at the bottom to write notes and stuff.
Sure. But I didn't know I use legal size paper or even what it is before I asked the apartment complex to print the lease agreement, and it didn't fit in their own folder with the other move in papers. In my rank of weirdness discovered upon moving to the US, this is at about the same level as the different ounces.
Why are two slightly different standards needed? Does legal really need to print "just a little bit more" text than others? If so, why not just use that one for everything?
It is no more confusing to Americans than the fact that Europeans use A4 is to Europeans. Why should it be? Just like you didn’t know standards other than A4 exist, Americans don’t think about the fact that standards other than 8.5x11 inches (I.e. letter) exist. All printers, binders, folders, hole punchers, etc. are made with letter size paper in mind, and most people unless they are involved in business with other countries have never encountered an A4 sheet of paper in their lives and probably have no idea other standards exist.
A0 is 1 square meter
An to An+1 means cutting the paper along the middle of the longer edge
Each An has the same aspect ratio
Those are pretty useful properties and precisely define the dimensions of A4.
Like a lot of mathematics it does matter in your daily life but you actually just don't think about it because of course this works - unless you're an American and so no it doesn't.
The A-series paper sizes mean everything scales very naturally. Poster? Pamphlet? It's just the same ratios again but bigger or smaller. There is a single design where this works, and that's why the A-series exists, you can't just pick anything, only this works.
I'm not trying to be combative; I genuinely don't know.
This feels obvious - of course it works like that, until your paper sizes aren't using this ratio (which the US ones don't) and then the frustration is apparent.
Like the fact that the aspect ratio chosen allows manufacturers to just use one base sheet and then subdivide it into smaller page sizes is convenient for manufacturers, but it's not a necessary property for scaling the contents of the page.
Same for printing two copies per page (2-up). With a 1:√2 ratio, you can perfectly fit two copies of something side-by-side on the same paper size. This was incredibly common back when I was at school, where A4 worksheets were printed 2-up on A4 paper so that each individual one was A5 in size (half the area, √2/2 the length). With A4, you then just chop the printed pages in half and the worksheet fits perfectly. With any other aspect ratio, either there'd be wasted space due to the different aspect ratio of the chopped-in-half paper to the original, or you'd have to print 4-up on larger paper and chop it into quarters. The 1:√2 aspect ratio of ISO paper sizes means you can just chop a page in half and get the same aspect ratio, and that's useful to people doing printing, not just manufacturers.
But if you really think it’s important, then you can consider a series of sizes like tabloid, letter, and memo to be equivalent to A3, A4, and A5. Each is exactly half the area of the previous, and can be had by dividing the larger size in half along the longer side.
This seems like you entirely missed the thread? The whole point is that this actually works for the A-series and in your made up US series it can't work because the ratio is wrong.
Let's try, start with 216 x 279 Letter and we'll scale that so we can fit two on the 279 long side, so they're just under 140mm wide now, memo size, but um, when we do that the scaled down pages are only 180mm high, even though they've got 216mm - there's a huge amount of empty white space wasted (at the top, or the bottom, or both) and that's because this ratio does not work.
Plus the copiers are a bit more clever than you give them credit for. Instead of scaling the whole page down they put a bounding box around the actual content on the pages, to exclude the margins, and then scale that down to fit. The size of the margins changes slightly but not enough that anybody cares. This is especially true when you’re copying a bound book because there’s a really big margin in the middle to accommodate the binding. You don’t need that any more once you’ve printed the pages on a single sheet of paper.
You can derive letter paper with two pieces of information: 8½ and 11. Just having a laugh, of course — I do admire the A/B series, even if I wish that they were based on a square yard :-)
A4 folded in half (size of an A5) fits in a C5 envelope.
An ISO standard that makes sense and isn't based on different professions like "letter" vs "legal" vs "folio" and other US sizes.
But also the reason that, for example, screens have 80 columns, (also related to punch cards), but that was about the width of a "letter" page at 10cpi.
Well, A4 (and variants) are not Europe-specific formats, it's the formats most of the world except some few countries (including the US) use, so I'd say it's slightly more surprising than the other way around.
Even if every other country in the world used A4, the only people in the US who would even notice would be people who commonly do business with other countries or who live near the border. And in reality, Canada and Mexico also use letter so the border thing doesn’t apply.
So why should letter confuse us just because other people use something else?
That's the part I initially quoted; "the paper that the text was printed on wasn’t an A4, it was smaller and not a size I was familiar with. I measured it and found that it’s a US letter size paper at about 21.5cm x 27.9cm"
The author isn't from North America, so they had forgotten the format was different, so they got confused when they assumed it would have been A4 like the rest of the world, but it wasn't.
> the only people in the US who would even notice would be people who commonly do business with other countries or who live near the border
Or, as in the case of the author, they live outside of North American and send/receive letters to/from North America.
Good thing it wasn't a complaint then, just questions from someone who doesn't know how it works across the pond :) And it seems to be the story of someone outside of North America trying to interact with the North American standards, not some internal confusion between internal states or whatnot.
Yes, it is just our standard like A4 is yours. When you pull a paper out of the pack it is A4 when we pull it out it is ANSI A, commonly known a US Letter size. Instead of 8.27”x11.69”, we use 8.5”x11”. We also commonly use US Legal size, which is 8.5”x14”. Slightly longer and can fit in the same envelope.
> do printers sold in the US default to US letter sizes when printing?
Yes. However all of our printers can do all sizes since our paper is slightly larger, while an A4 specific printer couldn’t print a US letter.
Margins on left/right might be skinnier, but length wise US letter fits.
My current printer, like most printers I believe, can be configured to print custom sizes. The maximum is something like 9 or 9.5 inches wide IIRC, and the length can be set much longer.
I can guess why the Philippines uses ANSI sizes. But Chile?
Or you can get whatever you want - I wanted B4 paper to print a booklet (or B3 maybe) and I just bought a ream that was larger and had a print shop slice it down to B4. My US laser printer was fine printing onto B4.
We just bought new ones when needed.
One particular “standard” that sticks out in my memory was “math paper”, which I recall as being unbleached, about 5” x 8”, and used pervasively in primary education (at least in New England) into the 1990’s.
My general point is just that I'm surprised so many people seem to notice and care about paper size in general. I've just never thought about this at all.
But, yes, for most people it doesn't really matter - you go to the store, you buy paper, you shove it into your printer, and it mostly just works. However, it's also not all that hard to run into situations where things break. E.g. most PDFs originating from US are rendered for Letter size paper, which means that printing them outside of US generally requires setting "fit size" rather than "original" to ensure that nothing gets clipped. Vice versa also happens, but because US is so culturally dominant, Americans rarely run into that particular issue.
A4 is readily available in the US but not commonly used.
The main problem is that if you cut it in half, you get a really silly sizes (too narrow) instead of A5.
I found out that they do not automatically adapt to JIS sizes. My wife’s work once had a printer that somehow got configured to use JIS, I assume JB5. It then refused to print on US Letter, but as printers are wont to do, didn’t produce any useful error message, nor relay this information to the computer. It just wouldn’t print. I only discovered this (because if you work in tech, you must know how to fix printers, right?) by laboriously scrolling through every menu on the tiny LCD screen, and finding that the paper settings were incorrect.
You kid, but it turns out the assumption was correct in this case. I suppose the truth is that by working in tech, you are likely very methodical and rely on deduction, which are both essential in fixing printer issues.
I don’t know when or why this skill declined, but it’s upsetting.
I am familiar with A4, A5 and such. But I think that fewer and fewer people are. It's just not something used every day.
As a side note, most of the big important house bills and statements I still insist on receiving via US mail for protection reasons. There is a risk if I only had them emailed to me that my wife would not have access. If I were to suddenly die, I don't want my wife with our kids to miss a critical bill. By having them show up at the house in physical form provides a bit of defense in depth here.
Letter size is 8-1/2 x 11 inches by US standards.
Yes, the default printing paper for US is US Letter. I prefer to use my computers with US English language, and macOS defaults to US Letter as print and page size when you use US English as the default language.
Moreover, I had a ream of US Letter paper in the past, given me by our neighbor (I live in a A4 country, so it's that "odd" size).
8.5 x 11” is US Letter, or 215.9 x 279.4 mm. We also have US Legal, which as the name implies, is frequently used by legal professions. I have no idea why. It is 8.5 x 14”, or 215.9 x 355.6 mm. Finally, we have US Tabloid (I guess used for small newspapers?), which is 11 x 17”, or 279.4 x 431.8 mm.
And yes, our printers default to US Letter. The line from the movie Office Space: “PC Load Letter? WTF does that mean?” is the printer’s cryptic way of saying “Load Letter-sized paper into the Paper Cassette.”
EDIT: there are are apparently more US-specific sizes I was unaware of, which you can view and compare with others on this site: https://papersizes.io/us/
I guess I shouldn't be surprised that the US and some other countries decided to do things differently... As a European, I don't think I've ever seen something not A4 or A3/A4 in a professional context in my life, ever. Are US letter sizes what people use instead of A4 in a workplace for documents and such (seems confusing if so), and do printers sold in the US default to US letter sizes when printing? Or just happens to be something FSF only seem to be doing?